Electric water heater



Aug. 23, 1927. f m

' `s. D. NEsMnH ELECTRIC WATER HEATER (www AMHA s `Filed Aug. 26. 1924 y f gwn@ AML/ELO /YESM/r'* atto! un* Patented ,'ug. 23, 1927.

UNITED STATES PATENT ori-ICEl SAMUEL D. NESMITH, OF SAN DIEGO, CALIFORNIA, ASSIGNOR OF PART INTEREST T0 A. S. BRIDGES, J. B. OSBORN,`MRS. KATHRYN OSBORN, JfH. BULMER, AND MRS. MARY E. NESMITH, ALL 0F SAN DIEGO, CALIFORNIA; ROGER TIIETLLESANLD` R. R. RICHARDSON, BOTH OF THE UNITED STATES NAVY; E. J. CALLAI-IAN, OF GUADA- LAJARA, MEXICO; GEORGE H. SCHMIDT, "WALTER C. STITT,`F. F. GRANT, H. '.Ml SAMMIS, :PAUL J. HARTLEY, AND R. C. EASOM. i

ELECTRIC WATER HEATER.

Application led August 26, 1924. Serial No. 734,254.

My invention relates to electric water heaters, and the objects of my inventionare: first, to provide an electric heater of this class having a plurality of flat, vertically positioned, water conducting channels positioned side byv side and parallel to each other, and which are heated by means of electric heating elements positionedV contiguous to and between the adjacent water conducting channels and insulated .therefrom, the heater being provided with water conductors communicating with the lower and upper ends of all of the water conducting channels thereof, whereby a large volume of water will pass through the channels with a minimum amount of resistance and be quickly heated therein; second, to provide a water heater of this class which is provided at its upper and lower ends with water passages increasing in cross-sectlon from the one side to the opposite side to which the respectiveA inlet and discharge conductors are connected, which passages communicate with the upper and lower ends of the water conducting channels, thus reducing to a minimum the resistancev of the water passing therethrough and providing means to permita large, continuous, substantially uninterrupted flow of water through the heater; third, to provide tubes for a heaterof this class, the thickness of the walls of which is such as to uniformly conduct the desired amount of heat to the interior of the water channels; fourth, to provide a substantially instantaneous and efficient electric water heater of proportionately largevolume; fth, to provide a novelly constructed water heater of this class, and sixth, to provide an yelectric water heater which is simple and economical of construction, durable, and which will not readilyv de-` teriorate or get outof order.

lVith these and other objects in view, as will appear hereinafter, my invention consists of certain novel and practical features 'of construction, combination and arrangement of parts and portions, as will be hereinafter described in detail and particularly set forth'in the appended claims, reference being had to the accompanying drawings and to the characters of reference thereon,

which:

which form a part of thisapplication, in

' Figure 1 is a front elevational view of my electric water heater, with the front wall of the casing and certain other parts and portions broken away and in section to facilitate the illustration; F ig. 2 is a sectional elevational viewthereof, with the section taken through 2 2 of Fig.V l, and Fig. 3 is a front elevational view thereof, with a portion of the front wall of the casing broken away and in section.

Like. characters of reference refer to similar parts and portions throughout the several views of the drawings.

The water tube supporting members 1 and 2, end wall members 3, water tubes 4, end water passage members 5 and 6, bolts 7, in-

let conductor 8, discharge conductor 9, cores 10, electric heating elements 11, insulating material 12, terminal posts 13, electric insulating plates 111, terminal Connecting members 15, nuts 16, electric conductors 17 and 18, heat insulating `materia-l 19, and the heater casing 20, constitute the principal f parts and portions of my water heater structure. y

The water tube supporting members 1 and 2 of my water heater are identical in construction, but positionedrin reverse order in horizontal positions, and are supported in spaced relation with each other at their ends by means of the end wall members 3. Extending vertically between the members 1 and 2 are the water tubes 1, which eX- .tcnd through Vsaid members and are welded or. riveted over at their projecting ends. These water tubes 4 are preferably made of flattened copper tubing of large diameter,

' same direction.

drawings. The members 5 and 6 are provided with large chambers or passages 5 and 6a, which communicate directly with the lower and upper ends of the water tubes fl, rIhe one end of the passage member 5 is provided with a large inlet conductor 8, and the one end of the water passage member 6 is provided with a large discharge conductor 9. rIhe width of each of the members 5 and 6 is substantially the same as the width of the water tube. The cross-sectional area of the passages 5a and 6 of the members 5 and 6, respectively, at the ends thereof connected with the conductors 8 and 9, is substantially equal to the eross-sectional area of all the water tubes combined, the depth of the passages decreasing gradually vtoward the opposite ends of the members 5 and 6, so that the cross-sectional area at any place within the passa-ges is substantially equa-l to the sum of the crosssectional areas of the water tubes on the opposite side of the plane, where the crosssection is taken, from the conductor connected with the particular passage. Thus, the resistance of the water flowing through the end passages and the tubes is reduced to a minimum. Io provide a gradually decreasing passage in the end members 5 and G, as described, the outer or bottom and top walls of the members 5 and 6 are of necessity inclined with the hori- Zontal plane. To provide a rectangular construction for the hea-ter, I have provided ribs 5b and 6l on the outer sides of the vinclined walls, one at the front and back edges thereof and one at its middle portion, so that the heater assumes a rectangular shape, as shown best in Figs. l and 2. The members 5 and G, it will be noted, are of ident-ical construction but positioned in reverse order relatively to each other. Between the side water tubes t and the end wall members 3 is provided heat insulating material 19, as shown bestI in Fig. 1.

It will be seen, therefore, that I provide headers at each end of the heater to which the water tubes are individually or independently secured, these headers providing water passages of gradually varying capacity, the water passage in the header at one end of the tubes gradually and uniformly increasing in capacity while the header at the opposite end of the heater uniformly and lgradually decreases in capacity in the Thisprovides a construetion whereby the formation of air pockets or steam pockets in the hea-ders will. be eliminated while at the same time the minimum resistance is roffered t0 the flow of water through the heater.

Each electric heat-ing unit of my water heater consists of electric heating elements ll wound around a core l0 of electric insulatingmaterial and molded in a casing l2 of heat conducting and electric insulating inaterial, preferably alundum. At the ends of the heating` elements ll are provided outwardly extending terminal posts 13, which L...J/end through the molded casiugs l2 and an elec ric insiilating plate la, one of which is positioned at the front and another at the back side of the heater. 'Ihe terminal posts 125 of each unit are connected with the corresponding post of the adjacent and separately positioned heating elements by means of the connecting members l5 and the nuts I6.

The water heater is preferably enclosed by means of a sectional casing 2O consist ing of the front casing member Q0, covering preferably the front, top and side walls of the heater, and the rear casing member 20", covering the bach side of the heater. Between the end passage members 5 and 6 and the sides of the heater, and the enclosing .casing 20, is preferably positioned a heat insulating' material 19 to confine the heat within the heater.

It is obvious from this construction, as illustratedin the drawings and disclosed in the foregoing specification, that there is pr0- vided an electric water heater as set forth in the objects of the invention and throughout the specification, and though I have shown and described a particular construction, combination and` arrangement of parts and portions, I do not wish to be limited to this particular construction, combination and arrangement, but desire to include in the scope of my invention the construction, combination and arrangement substantially as set forth in the appended claims. l

I-Iaving thus described my invention, what I claim as new and desire to secure by Letters Patent is: i

l. In an electric water heater, the combination of tw@ lr headers, one at the top and one at the bottom of the heater, a plurality of vertically extending, spaced apart, flattened water tubes extending from one header to the other and com]nunicating with the interiors thereof to connect said tubes in multiple tlufough said headers, electricallyinsulating heat-conducting material providing electrical heating elements interposed between each pair of adjacent water tubes, end plates at the ends of said heaters adjacent the end tubes, said end plates being bolted to the headers, heat-insulating material interposed between said end plates and the adjacent tubes, electrically-insulating side plates provided at each side of said heater, a casing for said heater and heatinsulat-ing means interposed between said casing and said heater.

2. In an electric water heater, the combination of two headers, each of which is of gradually and uniformly varying cross sec tion, end or spacer plates bolted to said headers and connecting said headers to each other, a plurality of flattened, verticallyextending Water tubes extending from header to header and communicating therewith, said tubes being independently secured to said headers and arranged in spaced relation to each other, electrical heating elements, independently removable, mounted between and adjacent each pair of Water tubes and electrically insulated from the tubes, removable electrically-insulating plates excasing for said heater and heat-insulating material interposed between said outer oasing and said end plates, headers and side insulating plates.

ln testimony whereoi, I have hereunto set my hand at San Diego, California, this A2nd dayv of August, 1924.

SAMUEL D. NE SMITH. 

